The AC Series takes power filtration to the next level. Built on a best-selling platform with a 40-year reputation for exceptional quality, reliability, and convenience, this series has become a standout choice that aquarium enthusiasts know and trust. Along with its proven multi-stage cleaning, CycleGuard beneficial bacteria support, and patented refiltration system, the latest clip-on generation sets a new standard for cleaning performance, media efficiency, quiet operation, and durability with several notable upgrades. Experience the unmatched cleaning power of Fluval HOB AC Series backfilter!Features 4-stage filtration (2 x mechanical, chemical, biological) for superior water clarity and quality CycleGuard preserves the biological balance of your aquarium through independent media replacement, which avoids disrupting the nitrogen cycle and is essential for maintaining clean and healthy water Patented refiltration system prolongs media contact time for a cleaner, healthier and more biologically stable aquarium Direct access to chemical media – no need to remove basket from filter (less mess) Pre-filter intake strainer keeps algae filaments and debris away from pump for consistent water flow High-porosity 30PPI mechanical foam for improved filtering capability Adjustable flow control for precise adjustment Quick and easy maintenance – reconfigured media basket design offers a dedicated space for each cleaning stage, allowing for faster and simpler changes Re-engineered rotor configuration enables smoother rotations, reduced vibration and quieter operation Molded rim connection for easy installation and leveling All media included Made in Italy For use in freshwater and saltwater aquariums What’s Included AC70 Power Filter Pre-filter Sponge Bio-Foam BIOMAX Activated Carbon The AquaClear AC70 Power Filter is ideal for 40 to 70 U.S. gallons aquariums. Fluval AquaClear AquaClear # BFA Item # AC70 Power Filter 19615 HA19615 Sizes available : AquaClear AC20 Power Filter, 76 L (20 U.S. gal) replaces A-595 AquaClear AC30 Power Filter, 114 L (30 U.S. gal) replaces A-600 AquaClear AC50 Power Filter, 189 L (50 U.S. gal) replaces A-610 AquaClear AC70 Power Filter, 265 L (70 U.S. gal) replaces A-615 AquaClear AC110 Power Filter, 416 L (110 U.S. gal) replaces A-620 BFA recommends that you do not use Ammonia Resins in Saltwater Aquariums. INSTRUCTIONAL MANUAL & WARRANTY